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Note 6 - Capital Stock, Stock Plans, Warrants, and Stock Based Compensation - Black-Scholes Valuation Model Assumptions (Details) - $ / shares | Jul. 28, 2016 | May 15, 2016 | Sep. 17, 2015
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Employee Stock Option [Member] |  |  |  |
Weighted-average fair value per share (in dollars per share) |  |  | $ 2 |
Risk -free interest rate (1) | [1] |  | 1.27% |
Expected volatility of stock (2) | [2] |  | 53.12% |
Dividend yield |  |  | 0.00% |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term | [3] |  | 6 years |
Director Stock Options [Member] |  |  |  |
Weighted-average fair value per share (in dollars per share) |  | $ 3 |  | $ 2.84
Risk -free interest rate (1) | [1] | 1.52% |  | 2.21%
Expected volatility of stock (2) | [2] | 55.99% |  | 57.98%
Dividend yield |  | 0.00% |  | 0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term | [3] | 10 years |  | 10 years
[1] | The risk-free interest rate is based on the U.S. Treasury yield in effect at the grant date over the expected term of the option.
[2] | The expected volatility is based on historical volatility from our traded Common Stock over the expected term of the option.
[3] | The expected option life is based on historical exercises and post-vesting data.

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- Definition Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award. + References No definition available. + Details
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iv) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.D.2) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 + Details
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